Releasing tap holder



. proaches Patented Nov. 9, 1943 v 233336 1 v V 1 RELEASINGTAP Holman} H Oskar Kylin, Cleveland Bardons andflliver, Inca ClevelandfOhio, a j

corporation of Ohio Heights,'0hio,'assignor to 1 Application December 14, I BdZLSerial N 469,029 '4 -1 Claim. (cine-'89 The present invention is an -improvement'in tap holders and relates more particularly to -the type adapted for use on turret lathes or other machine toolsl 7 It is one of the objects of my invention to provide a tap holder in which is embodied a sensitive release mechanism for releasing the tap in the holder whenthe tap reaches the end of its journey into the work piece to thereby permit the tap to rotate freely with the work and to prevent damage or destruction of the tap.

Another object of the invention is to provide a ing, the

be either a right: or left handed tap as required for the .operation onjthe work; piece. The tap holder comprises essentially relatively rotatable releasing tap holder of the above named character which is extremely simple in" construction and positive in operation.

Another object consists in providing a tap holder of the-releasing type which can be use with either right or left hand taps.

A further object of the invention is to provide means whereby the tap can easily be aligned with the opening in the work piece which is to be tapped.

A still further object is to provide a releasing tap holder which is automatic in its'operation.

Other objects and advantages of my invention will become more apparent as the following description of one embodiment thereof progresses, reference being made to the accompanying drawing in which like reference characters are employed to designate like parts throughout the same.

p In the drawing:

Figure 1 is a side elevation of a tap holder embodying my invention.

Figure 2 is a. similar View slightly enlarged and partly broken away to illustrate the relative'positions of the parts during a tapping operation and prior to the release or the tap for rotation with the Work.

Figure 3 is a rear end view of the tap collet detail.

Figure 4 is a transverse section taken in the direction of line 4-4 of Figure 2, and illustrates the positions of the parts as the tap is performing its operation in a workpiece.

Figure 5 is a fragmentary view of the parts shown in Figure 4 as viewed in Figure 2. I

- Figure 6 is a section similar to that in Figure 4,

the end of its working travel. Figure '7 .is a fragmentary view of the parts shown in Figure 6 as viewed in Figure 2.

Figure 8 is a section similar to that of Figure 4,

' but shows the positions of the parts when the tap is released in the holder for rotation with the work.

Figure 9 is a view similar to Figure "I, and, Figure 1G is a top view of the lockin pin. Referring now more specifically to the drawshowing the positions of the parts as the tap' a pparts.andassociatedmeans for locking theseparts against lrotation during the tapping operation,

but automatically v permitting relative rotation instantly the tapv hasrreached the limit pi its travel in the work piece. The shank I terminates in a slightly enlarged head 3 having an opening or here 4 extending transversely ofthe axis of the shank'and terminating at one end in a reduced diameter as. at. 5.- VA releasable locking members is slidable inthe bore 4 and is normally thrust outwardly of the, boreby meansof a compression spring].

i As shown in Figure 2, the spring 1 is di posed axially 0f the bore 4, one. end of the spring abutting "the lower inclined wall 8 of the bore which terminates in a smaller, opening 5, while a portion of the spring extendswithin the hollowed portion of the, locking memberli to engage at its upper end with. the head portion of the member. A slot 9 isformed. in the side of the locking member and extends upwardly fromthe bottom open end thereof and isaadapted to slidably receive the transverse guide pin lllprojecting radially inwardly from'the head 3...It will be seen that the locking member .16. is movable re.-

dially of the axis of theshank and is urged in such movement in one direction by the action of v the spring 1 while it is movable in the opposite direction against the compression of the spring.

Movement of the locking member is restricted to a strictly radial direction in either case, rotative 40' movement thereof being preventedby the guide pin 10 projecting within the slot 9. This is necessary due to the structure of the locking member external head portion and its functions and relation to other parts of the tap holder-which will 'be described presently.

Ihe tap 2 is removably clamped in a (pellet; or chuck comprising a body 'I l having a reanwardly extending cylindrical portion I2 which is adapted to receivethe enlarged head 3 and locking memberflassembly. The outer wall is threaded at l 3 to receive the threaded end'of a sleeve 14 {When the sleeve isin proper position on the'bod y; l I,

; its inturned annular flange liabuts the rear end of the cylinder as at 16. Aswili be seerr -frorn the drawing, the flange 15 s spaced'slightly from thej'shank at l! whilethe circumferential wall of the .head i 3 has sliding and rotational bearing engagement with the inner wen or the cylinder [2. The body l l is limited inits axial movement on embodiment illustrated is of the type -which .is.adapted to clamped in a turret head by meansof a clamping belt operating against the shank; l. by'which; the unit is supported in the turret head. The tap is indicated at 2 and may 

